Nitroguanidine products

Nitrogen tribromide, 4 319 Nitrogen trifluoride, 22 830 production of, 22 845 Nitroglycerin[e] (NG), 9 47, 48 10 730 molecular formula and structure, 5 110t pharmacokinetics, 5 115 processes, 27 164 production of, 27 174 Nitro group, 27 157-158 Nitroguanidine, 20 734 Nitrol, molecular formula and structure, 5 1 lOt... 

Dagley and co-workers reported the synthesis of 2-nitrimino-5-nitrohexahydro-1,3,5-triazine (100) from the Mannich condensation of nitroguanidine (98), formaldehyde and t-butylamine, followed by nitrolysis of the t-butyl group of the resulting product, 2-nitrimino-5-fert-butylhexahydro-l,3,5-triazine (99). The triazine (100) has also been synthesized from the reaction of nitroguanidine and hexamine in aqueous hydrochloric acid, followed by nitration of the resulting product (97) with a solution of nitric acid in acetic anhydride. ... 

Nitroguanidine (NQ) is a nitramine compound containing one N-NOj group in its molecular structure. In contrast to cyclic nitramines such as HMX and RDX, its density is low and its heat of explosion is also comparatively low. However, the Mg of its combustion products is low because of the high mass fraction of hydrogen contained within the molecule. Incorporating NQ particles into a double-base propellant forms a composite propellant termed a triple-base propellant, as used in guns. 

Triple-base propellants are made by the addition of crystalUne nitroguanidine (NQ) to double-base propellants, similar to the way in which nitramine is added to CMDB propellants as described in the preceding section. Since NQ has a relatively high mole fraction of hydrogen within its molecular structure, the molecular mass of the combustion products becomes low even though the flame temperature is reduced. Table 4.13 shows the chemical composition, adiabatic flame temperature, and thermodynamic energy,/ as defined in Eq. (1.84), of a triple-base propellant at 10 MPa (NC 12.6% N). 

Nitroguanidine is reduced to aminoguanidine 24 in good yields using aqueous sulphuric acid as electrolyte when the product precipitates as the hydrogen sulphate [124,125], Nitrourea affords semicarbazide on reduction in acid solution [126]... 

This substance is an intermediate product of the decomposition of the important explosive nitroguanidine. It is also present in an aqueous solution of nitrourea or a sulphuric acid solution of nitrourea (Davis and Blanchard [7]). 

Jousselin [26] prepared nitroguanidine by the action of anhydrous nitric acid or sulphuric acid on guanidine nitrate. The preparation of this substance by the action of sulphuric acid has been developed as an industrial method for the production of nitroguanidine. The method described by Marqueyrol and Loriette [27] follows somewhat different principles. It consists in acting with anhydrous nitric acid on guanidine sulphate which, in turn, is obtained on treating dicyandiamide with sulphuric acid. 

Nitroguanidine exists in two crystalline forms. The a-form results from the action of sulphuric acid on guanidine nitrate followed by the precipitation of the product with water. This form crystallizes from water in long, fairly flexible needles. 

The apparent dens ty of the crystals is 0.96, whereas that of ordinary commercial nitroguanidine is about 0.25 and that of the product rapidly crystallized from methanol is about 0.40. 

Barton, Hall and Wright [42] found that the action of alkalis on nitroguanidine involves hydrolysis with the formation of ammonia, nitrourea and the products of the decomposition of nitrourea. 

Taking into account the results of experiments conducted with a manometric bomb as well as the chemical composition and specific heat of the products of decomposition Muraour and Aunis calculated the following values for the explosion of nitroguanidine ... 

The reaction solution should be diluted to 15% H2S04 keeping the temperature below 30°C o ensure full precipitation of the nitroguanidine. The product should be washed with an aqueous solution of ammonium carbonate and then with water at 15-25°C. 

Nitroguanidine occurs in a fine-crystalline form in which it is suitable for the manufacture of flashless propellant. A different form of nitroguanidine is used as a high explosive. When it is to be compressed, its solution is rapidly evaporated under reduced pressure to form a specially fine-crystalline product. 

According to these authors, nitrosoguanidine is prepared by the reduction of nitroguanidine with zinc dust in a neutral medium, in the presence of ammonium chloride at room temperature (below 20-25°C). The product is filtered off together with a precipitate of zinc oxide and zinc salt, from which it is then extracted with hot (65°C) water. Nitrosoguanidine crystallizes when the solution is cooled to 0°C. The yield is about 50%. 

The explosive properties of the potassium salt of nitrocyanamide first attracted McKay s [37] attention. He separated this potassium salt as a by-product from the preparation of aliphatic diazo compounds by the hydrolysis of N-alkyl-N-nitroso-N -nitroguanidines with an aqueous solution of sodium hydroxide at temperatures from 0°C to room temperature ... 

X = S) is excluded on the basis of the reduction of the corresponding ureas (143) to the known 3-aryl-l-(isopropylideneamino-amidino)ureas (143a R = Ph). In the absence of rearrangement, the condensation products of isocyanates and nitroguanidine may thus be formulated as nitramines (143), and, by analogy, their sulfur analogs as 139.141... 

Nitroguanidine may be prepared by the nitration of guanidine salts by means of nitric acid,1 or by the action of concentrated sulfuric acid upon guanidine nitrate.2 The nitration of guanidine thiocyanate yields a product which retains a small proportion of sulfur compounds, and Lhe nitration of the sulfate requires vigorous treatment and gives poor yields. The present procedure, which yields the alpha form,3 is simple and economical, and furnishes a good yield. 

Uses. NC isused in single-base, smokeless propellants(NC non-expl ingredients) double -base, smokeless proplnts(NC NG) triple -base, smokeless proplnts(NC, NG nitroguanidine) and in dynamites. Commercially NC is used in pharmaceuticals, lacquers, and photographic products(Ref 80)(For more detailed info on NC s, see various types of NC listed in Table and discussed separately, next page)... 

Preparation of a-Nitroguanidine. Five hundred cc. of concentrated sulfuric acid in a 1-liter beaker is cooled by immersing the beaker in cracked ice, and 400 grams of well-dried guanidine nitrate is added in small portions at a time, while the mixture is stirred with a thermometer and the temperature is not allowed to rise above 10°. The guanidine nitrate dissolves rapidly, with very little production of heat, to form a milky solution. As soon as all crystals have disappeared, the milky liquid is poured into 3 liters of cracked ice and water, and the mixture is allowed to stand with chilling until precipitation and crystallization are complete. The product is collected on a filter, rinsed with water for the removal of sulfuric acid, dissolved in boiling water... 

The production of nitrous oxide is not exactly quantitative because of secondary reactions. A solution of nitroguanidine in concentrated sulfuric acid, after standing for some time, no longer gives a precipitate of nitroguanidine when it is diluted with water. 

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